Compared to Nikon Coolpix 990 and Olympus C-3030ZContd.

Colour Chart Comparison

It's a close run thing. All cameras showing good daylight
white balance and good metering. There is little between the three cameras
in this test, the S70 producing slightly stronger colours.

We're only measuring colour here. RGB values below were
taken from a VGA reduced image (to average colours and eliminate JPEG
artifacts) using the Eyedropper tool in Photoshop with a 5 by 5 Average
Sample Size.

Sony DSC-S70

Coolpix
990

Olympus
C-3030Z

Patch White

182,182,182

201,201,201

197,197,197

Middle Gray

85,85,87

104,104,104

92,92,92

Patch Red

189,17,27

223,52,58

191,21,21

Patch Green

1,132,35

5,149,63

0,140,52

Patch Blue

33,26,123

60,50,112

56,41,102

Resolution Comparison

Shots here are of the PIMA/ISO 12233 standard resolution
test chart (more available for comparison in our comparison database).
Studio light, cameras set to auto, Exposure compensation +0.7 EV for all
cameras. How to read the charts: All values are 1/100 th lines/picture
height/width. So the "10" value equates to 1000.

Sony DSC-S70

Nikon Coolpix 990

Olympus C-3030Z

Measurable findings (three measurements taken for each camera):

Camera

Measurement

Absolute Res.

Extinction Res.

Sony DSC-S70

Horiz LPH

1050

1400

Vert LPH

1050

1500

5o Diagonal LPH

1000

n/a

Nikon
Coolpix 990

Horiz LPH

900

1300

Vert LPH

900

1400

5o Diagonal LPH

900

n/a

Olympus
C-3030Z

Horiz LPH

900

1350

Vert LPH

900

1350

5o Diagonal

900

n/a

Definition of terms:

LPH

Lines per Picture Height (to allow
for different aspect ratios the measurement is the same for horizontal
and vertical)

5o Diagonal

Lines set at 5o diagonal

Absolute Resolution

Still defined detail (below Nyquist
frequency*)

Extinction Resolution

Detail beyond camera's definition
(becomes a solid gray alias)

n/a

Not Available (above the capability
of the test chart)

n/v

Not Visible (not visible on test
results)

* Nyquist frequency defined as the highest spatial frequency
where the CCD can still faithfully record
image detail. Beyond the Nyquist frequency aliasing occurs.

Well, there you have it. The S70 definitely has more
resolution than its nearest competitors the Coolpix 990 and Olympus C-3030Z.
Sony have achieved this through the use of a good quality large factor
lens system and a quality in-camera processing algorithm.

Red Channel Noise

Not surprisingly the S70 produced very little red channel
noise in blue or light blue shades, certainly not as much as we'd seen
on the 990 and C-3030Z. Whether this is down to the CCD, electronics systems,
algorithms or JPEG compression it's there in the final image and therefore
becomes visible in certain circumstances. That said, this noise can be
corrected using third party tools.

The samples above are of 50 x 50 blocks cropped from
the colour comparison charts above of the Blue and Cyan patches, each
block is then broken down into it's red green and blue channels and reflected
as such directly below.